1. Field of the Invention
The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device which forms a plurality of linear pixel electrodes together with counter electrodes within a pixel region formed on one substrate out of a pair of substrates which sandwiches liquid crystal therebetween.
2. Background Art
This type of liquid crystal display device may be configured to apply an electric field having components parallel to a substrate to liquid crystal and such a liquid crystal display device is known as a liquid crystal display device which possesses excellent wide viewing angle characteristic (referred to as an IPS-type liquid crystal display device in broad meaning).
As this type of liquid crystal display device, when roughly classified, there have been known a usual IPS-type liquid crystal display device (also referred to as an IPS-type liquid crystal display device in narrow meaning in this specification), and a so-called IPS-Pro liquid crystal display device (being a kind of an IPS-type liquid crystal display device in broad meaning but different from an IPS-type liquid crystal display device in narrow meaning in structure).
In the former narrow IPS-type liquid crystal display device, as shown in FIG. 5A, for example, counter electrodes CT are also constituted of a plurality of linear electrodes in the same manner as pixel electrodes PX, and the plurality of counter electrodes CT and the plurality of pixel electrodes PX are arranged alternately in the direction which intersects the longitudinal direction of these electrodes as viewed in a plan view. While the plurality of counter electrodes CT and the plurality of pixel electrodes PX may be formed on the same layer as shown in FIG. 5A, the plurality of counter electrodes CT and the plurality of pixel electrodes PX may be formed on different layers by way of an insulation film although not shown in the drawing.
In the latter IPS-Pro-type liquid crystal display device, for example, as shown in FIG. 6A, a counter electrode CT is formed of a planar electrode, and a plurality of linear pixel electrodes PX are arranged above the counter electrode CT by way of an insulation film in an overlapping manner with the counter electrode CT. Different from the constitution shown in FIG. 6A, the pixel electrode PX may be formed of a planar electrode and a plurality of linear counter electrodes CT may be arranged above the pixel electrode PX by way of an insulation film in an overlapping manner
Here, both of the counter electrodes CT and the pixel electrodes PX may be formed of a transparent conductive film made of ITO (Indium Tin Oxide) or the like, for example, and hence, a numerical aperture of the pixel may be enhanced.
Here, as a document which discloses a technique relating to the present invention, WO 2005/006068 A1 (patent document 1) is named. A liquid crystal display device disclosed in patent document 1 is configured such that the IPS-type pixel constitution in narrow meaning and the IPS-Pro-type pixel constitution coexist in mixture within one pixel. That is, this liquid crystal display device is configured such that, for example, a transmissive region and a reflective region are provided within one pixel, and the transmissive region adopts the IPS-type pixel constitution in narrow meaning, the reflective region adopts the IPS-Pro-type pixel constitution, and counter electrodes are made of metal which exhibits favorable light reflectance efficiency.